Can my 3 month old son Naithan sleep in his crib while his five year old sister from another mother sleep in her bed in the same room? Is this legal?

I can't imagine there being anything wrong with that. I'm sure it happens it many homes. Being from Canada I don't know if there would be laws against that in other countries/states. Where do you live?

Don't see anything even wrong? There are few "laws" there will be rules in the US within each state Children and family Services dept that they may deem wrong.

But step children of varoius younger ages will often share rooms